1. Field of the Invention
The present invention relates to a device for affixing a trim cover assembly over a foam cushion member in order to produce an automotive seat or a vehicle seat.
2. Description of Prior Art
Generally, a vehicle or automotive seat comprises a seat cushion for receiving a passenger's buttocks and thigh portion and a seat back for receiving his or her back. Each of such two seat constituent elements is by and large composed of a foam cushion member forming a main body, a trim cover assembly affixed over the foam cushion member, and a seat frame embedded or inserted in the same cushion member. In most cases, the trim cover assembly is of a multi-layer lamination structure, as typically found in a three-layer lamination type trim cover assembly comprising a surface cover layer, a thin foam padding layer (e.g. a slab urethane foam material), and a back cloth layer.
In this sort of seat construction, the process for producing a resulting seat constituent element, namely, a seat cushion or a seat back, has been carried out, using such incomplete seat sub-assembly (SA') as shown in FIG. 9, which comprises a foam cushion member (P) and a three-layer lamination type trim cover assembly (C) fixed thereto in an overhang fashion.
The foam cushion member (P) illustrated in FIG. 9 is so formed to have a frontal surface (not clearly shown but understandable in FIG. 9) having a predetermined outer shape of a seat, an upper side wall portion (P1-a), two lateral side wall portions (P1-b)(P1'-b), a U-shaped reverse flat wall portion defining an upper reverse wall part (P2-1) and two reverse side wall parts (P2-2)(P2'-2), and lower wall portion (P3). All the inward edges of the upper and side reverse wall parts (P2-1)(P2-2)(P2'-2), thus, define a U-shaped cut-away area (P2-3). Also, the cushion member (P) has a hollow therein as can be seen from the designation (P4) in FIG. 9, which denotes an inner reverse wall, and also from FIG. 2. Though not shown, a suitable seat frame may be inserted through the cut-away area (P2-3) into the inner hollow of the cushion member (P).
The trim cover assembly (C) per se is formed from the following three layers: a surface cover layer (C1), a foam padding layer (C2) and a back cloth layer (C3) laminated in this order. But, in FIG. 9, the trim cover assembly (C) is shown as being turned upside down to expose upwardly the back cloth layer (C3), for a subsequent manual processing purpose. Normally, the trim cover assembly (C) is preformed from one unitary sheet of a three layer lamination structure, by sewing, into such a three-dimensional body as is understandable from FIG. 10, that conforms generally to a whole body of the foregoing foam cushion member (P). Such three-dimensional body of trim cover assembly (C) is turned over and fixed at its central area to the foregoing frontal surface of cushion member (P) to form what is called an "overhang" state, as can be seen in FIG. 9. This overhang form of trim cover assembly (C) comprises a central section (not seen from both FIGS. 9 and 10 but can be understood from the reverse side of the turned-over body thereof) fixed to the frontal surface of cushion member (P), an upper overhang section (C4) extending continuously from the upper side of the central section, a pair of lateral overhang sections (C5) and (C5') each extending continuously from both lateral sides of the central section, and a lower overhang section (C'). The upper overhang section (C4) is sewn, at its both sides, fixedly with the respective two lateral overhang sections (C5)(C5') as can be seen from the seam lines (SL)(SL').
A hook-like anchor member (F) is fixed at the end of the upper overhang section (C4), and two hook-like anchor members (F1)(F1) are fixed at both ends of the two lateral overhang section (C4). Those anchor members (F, F1) are adapted to be hookingly secured over a seat frame (not shown) which will be inserted in the hollow of cushion member (P).
As viewed from FIG. 9, the thus-preformed overhang form of trim cover assembly (C) exposes its back cloth layer (C3) outwardly and the central section of trim cover assembly (C) at the back cloth layer (C) is fixed to the corresponding central surface area of cushion member (P). This fixation is effected (P) through a bonding process or a foaming process. That is, in the bonding process, a worker should use a suitable adhesive to bond the central reverse-side area of trim cover assembly (C) to the corresponding central surface area of cushion member (7), with his hands, or in the foaming process, the turned-over trim cover assembly (C) is placed in a foaming mould used for forming the cushion member (P) and foamed with a foaming base material in the mould so as to integrally fix the central reverse-side area of trim cover assembly (C) to the corresponding central surface of the resultant foam cushion member (P).
Conventionally, this incomplete seat assembly (SA') with the trim cover assembly overhang sections (C4)(C5)(C5') (C') is processed manually by the worker, who forcibly turns those overhang sections (C4)(C5)(C5')(C') over towards the mating reverse wall portions (P2-1)(P2-2)(P2'2)(P3) of cushion member (P) in order to produce the resultant seat sub-assembly (SA) as in FIG. 10.
However, this manual operation has been very troublesome, imposing an extraordinary labor on a worker and further requiring a high hand force to him or her, because the expanding area or depth of the upper overhang section (C4) is naturally great to cover both upper side wall portion (P1-a) and upper reverse flat wall part (P2-1) and therefore, especially to turn over such upper overhang section (C4) up to those two portions of cushion member (P), requires a high hand force on the worker's part, leaving thus the problem that a physically weak worker with very small hand force can not turn over that upper overhang section (C4).